The present invention relates in general to household storage containers for produce. In particular, the present invention relates to a produce storage container having selective venting and an improved bottom panel structure.
In storing food in the household, the primary concern is maintaining freshness of the food. To maintain freshness, two main methods have been employed. The first is refrigeration, and the second is containment. These are typically, but not necessarily, used together for maximum effectiveness.
Refrigeration is, of course, the provision of a reduced temperature environment. This reduced temperature reduces the grown rate of bacteria and other organisms, slowing their degradation of the stored food. This is a well known arrangement.
Containment of food in an effort to maintain freshness has typically meant sealing the food against air exchange with the ambient environment, preferably at a reduced pressure. This has been achieved in numerous ways, such as by encasement within carefully folded aluminum foil, encasement within plastic bags which may be sealed, or placement within a plastic container having an air-tight seal. Such containers are typified in the assignee""s product, sold under the registered trademark TUPPERWARE.
While this storage method is excellent for certain food types, it has been found that this is not the best storage method for produce. Specifically, fresh produce continues to live for some time after harvest, including during the period the produce is typically consumed. This means that the produce continues to respirate and produce other gasses. Further, the trauma induced by harvest can often result in the respiration rate of the produce to increase, sometimes dramatically, over the respiration rate in the field. Relatively prolonged exposure to an excessive concentration of these respiration and other gasses may degrade the appearance, flavor, texture, or other aspects of the produce.
Sealing produce against air exchange, as described above, may be seen to simply trap the respiration and other gasses with the produce. Unless the seal is periodically broken to permit air exchange, buildup of an excessive concentration will occur, degrading the produce. To prevent this, several containers for produce have provided for gas exchange.
A first example is shown in U.S. Pat. No. 4,676,371 to Byrne. Byrne describes a produce storage container formed of an air-impervious material, but having several gas exchange openings. The openings are formed in a base of the container, and a lid is provided to close the top of this base. A second example is a product sold by TEFAL S. A. under the model name xe2x80x9cla lxc3xa8gumixc3xa8rexe2x80x9d. This product includes a base formed of an air impervious material, and having a lid. The lid is also formed of an air impervious material, but includes a pair of apertures extending therethrough and a sliding gate which may be manually moved to selectively block one of these apertures. The aperture may not be closed in a gas-tight manner, but does include a filter to prevent ingress of contaminants. Both of these containers may be used within a household refrigerator to increase the freshness of the produce through refrigeration.
An object of the present invention is to provide a container which will store produce with the maximum freshness for the maximum amount of time, by permitting gas exchange with the ambient environment.
Another object of the present invention is to provide such a container which may also be used in the convention manner with essentially no gas exchange.
A further object of the present invention is to provide a container which permits the amount of gas exchange to be varied between different levels for accommodating foods require no gas exchange, foods which required moderate gas exchange, and foods which require high gas exchange.
Yet another object of the present invention is to provide such a container which is well suited for use in a household refrigerator.
Another object of the present invention is to provide such a container which includes a base structure which reduces contact of the stored food with any condensate which may have accumulated within the container.
A further object of the present invention is to provide such a base structure which further serves to segregate such condensate into discrete areas to reduce cross-contamination between such areas, and to reduce shifts in the center of mass of the container.
These and other objects are achieved by a vented container for produce having a base and a cover which are at least substantially impervious to gas transfer. The base includes a base panel and side walls. Preferably two vent apertures are formed through the side wall, and a plug is provided for each vent aperture, to permit the vent apertures to be selectively opened. The plugs may be mounted upon vent toggles, such that manual pivoting of the vent toggles will open or close the associated vent aperture. The selective opening of the vent apertures permits gas exchange between the interior of the container and the ambient atmosphere, providing improve storage for produce. Maintaining the vent apertures closed permits the container to be used as a normal sealed food storage container. The base panel preferably includes an alternating series of hills and troughs to segregate condensate within the container. The troughs may be downward concave to further subdivide the condensate within each trough. The hills may include central depressions to act as traps to reduce condensate flow over the hills.